(a) A Natural Resources Department is investigating the total dissolved solids (TDS) in one of the rivers in Selangor. To be acceptable as drinking water, the mean TDS must be limited up to 500 mg/L only. Past record shows that the standard deviation of the TDS is 35 mg/L. (i) Set up the appropriate null and alternative hypotheses for safe drinking water. (ii) Find the critical region if the chance of rejecting the null hypothesis when it is true is 0.05 based on 50 samples? (iii) Calculate the power of the test if the alternative true value of population mean is 480 mg/L. (iv) Find the sample size required if the power of the test is 0.90 and the true mean 480 mg/L? (v) A random sample of 50 specimens give sample mean of 505 mg/L. Is the river meets the criteria for safe drinking water? Justify.

(a) A Natural Resources Department is investigating the total dissolved solids (TDS) in one of the rivers in Selangor. To be acceptable as drinking water, the mean TDS must be limited up to 500 mg/L only. Past record shows that the standard deviation of the TDS is 35 mg/L. (i) Set up the appropriate null and alternative hypotheses for safe drinking water. (ii) Find the critical region if the chance of rejecting the null hypothesis when it is true is 0.05 based on 50 samples? (iii) Calculate the power of the test if the alternative true value of population mean is 480 mg/L. (iv) Find the sample size required if the power of the test is 0.90 and the true mean 480 mg/L? (v) A random sample of 50 specimens give sample mean of 505 mg/L. Is the river meets the criteria for safe drinking water? Justify.

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Description: (a) A Natural Resources Department is investigating the total dissolved solids (TDS) in oneof the rivers in Selangor. To be acceptable as drinking water, the mean TDS must belimited up to 500 mg/L only. Past record shows that the standard deviation

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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